HD 113538

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HD 113538
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Centaurus
Right ascension 13h 04m 57.48s[1]
Declination −52° 26′ 34.5″[1]
Apparent magnitude (V) 9.057
Characteristics
Spectral type K9V[2]
B−V color index 1.376
Astrometry
Radial velocity (Rv) 39.23 ± 0.012[3] km/s
Proper motion (μ) RA: -785.48 ± 0.93[1] mas/yr
Dec.: -795.33 ± 0.80[1] mas/yr
Parallax (π) 63.03 ± 1.36[1] mas
Distance 52 ± 1 ly
(15.9 ± 0.3 pc)
Absolute magnitude (MV) 8.03[3]
Details
Mass 0.7 ± 0.1[3] M
Radius 0.65 ± 0.1[3] R
Luminosity 0.09[3] L
Surface gravity (log g) 4.28 ± 0.37[3] cgs
Temperature 4685 ± 155[3] K
Metallicity [Fe/H] −0.17 ± 0.074[3] dex
Other designations
Gliese 496.1/9425, HIP 63833
Database references
SIMBAD data

HD 113538 (Gliese 496.1) is a K-type main-sequence star of a late spectral type (K9V) that lies approximately 51 light-years away in the constellation of Centaurus. The star was announced to have a planetary system in 2010.

Planetary system[edit]

Radial velocity variation of HD 113538 was inferred from observations with the HARPS spectrograph. The star is active (Log R'HK −4.697,[2] SMW 1.05[3]), but the RV variation is not correlated with activity, indicating that planets are responsible. The data is fitted well by a solution including two planets, with an eccentric Saturn-mass planet and a more massive planet on a longer-period orbit—similar to the orbital architecture of the planetary system orbiting HD 163607, though with lower masses. Interestingly, similar to HD 163607 b, the eccentricity and argument of periastron of HD 113538 b increases the planet's transit probability substantially more than it would be on a circular orbit.

The HD 113538 planetary system[3]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b ≥0.27 ± 0.08 MJ 0.71 ± 0.01 263.3 ± 2.3 0.61 ± 0.11
c ≥0.71 ± 0.06 MJ 2.43 ± 0.06 1657 ± 48 0.32 ± 0.06

References[edit]

  1. ^ a b c d e van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. 
  2. ^ a b Grey et al., R. O. (2006). Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc-The Southern Sample. arXiv:astro-ph/0603770. Bibcode:2006AJ....132..161G. doi:10.1086/504637. 
  3. ^ a b c d e f g h i j Montou et al., C. (2010). The HARPS search for southern extra-solar planets. XXVII. Seven new planetary systems. arXiv:1012.3830. Bibcode:2011A%26A...527A..63M.